Twyer.



No. 725,742. Y PATENTED APR. 21, 1903. J. W. MILLER L M. WEBB.

TWYER.

APPLIOATION FILED rms. s, 190s.

no Monm..

' UNITED' STATES JAMES V. MILLER AND MICHAEL VEBB, OF JOLIET, ILLNOIS.

TWYER.

SPECIFICATION forming part of Letters Patent No. 725,742, dated April 21, 1903.

Application filed February 9, 1903. Serial No. 142,548. @lo model.)

To all whom, t may concern.-

Be it known that we, JAMES WV. MILLER and MICHAEL WnBB,citizeus of the United States, residing in the city of Joliet, county of Will, and State of Illinois, have in vented a new and useful Improvement in Twyers, of which the following is a specification.

Our invention relates to twyers for blastfurnaces; and the objects of the invention are, first, to provide a twyer which shall have a high resistance to the action of heat, and, second, to provide means for protecting the twyer from abrasion during the insertion into or withdrawal from the wall of the furnace and from abrasion by the ores and fuel Within the furnace. Ve attainvthese objects by the device illustrated in the accom pauying drawings, in which- Figure lis avertical section showing a suitable arrangement of the twyers and adjuncts in a furnace. Fig. 2 is a sectional view of a twyer,taken longitudinally on the central axis thereof; and Fig. 3 is a transverse sectional View taken on the line 3 3 of Fig. 2.

Similar reference characters denote similar parts throughout the several views.

a a represent the inner Walls of the furnace, usually constructed of fire-brick. b b are the outer walls, supported on the posts c c. Said inner walls areapertured at their lower portions for receiving the twyers, through which the air-blast is forced into the furnace. The air is supplied to the twyers from the down-pipes d, leading from the bustle-pipes e.

In our improved twyer, f' represents the central duct, which is inclosed within the preferably cylindrical and concentric metallic walls g and h. Said' walls are connected at their extremities, thereby forming a shell, and by means of the pipes t', connected to the outer extremity of the said shell, water is cireulated through the twyer to cool the same. At a point preferably about six inches from its inner extreinity'the smaller inner Wall g has an offset j, thereby forming an annular recess for receiving the inner fold la 'of the insulating material k. l-In a similar manner the outer Wall h has an offset m near its outer extremity, andthe outer fold of said insulating material abuts the same. The widths of said osets j and m are nearly equal to the thickness of said insulating material.

The extreme outer portion n of the twyer preferably flares somewhat to facilitate connection with the nozzle of the down-pipes d.

Theinsulating material 7c consists, preferably, of asbestos com position, silica-cement, or fire-clay, and the inner and outer folds k and 102 are brought around the inner end of the twyer, so that the insulation is continuons and free from joints.

When in use, substantially the whole of such portion of the twyer as has the straight cylindrical sides lies within the furnace-Wall. In our twyer theA sheathing o incloses the outer fold 7a2 and preferably also the end and the inner fold of said material. Said sheathing is composed of thin sheet or cast metal, aud the relative thicknesses of the parts are such that when the sheathing is in place the inner surface of the twyer is substantially smooth and continuous.

It will be understood that in a blast-furnace the heat at the point where the twyers enter is very great, and with the ordinary twyers now in use frequent renewals are necessary. The loss incurred with the present shortlived twyers is not merely in the cost of the labor and material involved, but the cooling- Water entering .the furnace is apt to do considerable damage. The life of our twyer is greatly prolonged, for the reason that the direct heat of the furnace cannot reach the inner metal, which forms the Water-chamber, and the cooling-water prevents the temperature of the metalfrom approaching the melting-point. The protect-ion due to the insulating material is not confined to the outside and the endof the twyer, but is afforded to the exposed portion of the inside also.

Thetwyer should fit somewhat closely in 'the furnace-wall, and the'insulating material, although having a great resistance to heat, has comparatively small resistance to abrasion. By means of said outer sheathing 0 the twyer may be forced into the Wall Without danger of injuring the insulating material. Furthermore, the sheathing at the end and interior surface of the twyer protects the insulation from the abrasive action of the ores and fuel passing through the furnace. Although the sheathing itself isccmparatively thin, it maintains its constituency for a considerable period, for when a small mass of IOO Y away.

molten metal strikes it and melts a portion thereof the said metal becomes cooled sufficiently to build up on the sheathing and supply an equivalent of the amount burned Thus there is a continuous substitution more or less perfect, and by this means the life of the sheathing is considerably prolonged.

Having thus described our invention, what We claim as new, and desire to secure by Letters Patent, is

l. A twyer consisting of a metallic shell and two folds of insulating material joined together at the inner extremity to form a continuous covering for said shell.

2. In a twyer, the combination of recessed or offset inner and outer walls; and insulating material covering the oset portions of said Walls and the inner extremity thereof, and said insulating material abutting the offsets in said Walls.

3. In a twyer, the combination of a metallic shell, two folds of insulating material joined togetherat the inner extremity to form a continuous covering for said shell, and a sheathing of metal inclosing said insulating material for the purpose described.

4. In a twyer, the combination of recessed or offset inner and outer walls forming a metallicshell, insulating material covering said shell and abutting the oset inthe inner one of said walls and a metallic sheathing covering said insulating material and also abut-- ting the offset in the inner one of said Walls, the surface of said sheathing being flush with the inner surface of the twyer thereby forming a substantially smooth and continuous inner duct.

5. In a twyer, the combination of recessed or oset inner and outer walls forming a metallic shell, pipe connections to said twyer for supplying cooling-Water within the shell, insulating material covering said shell and abutting the offset in the inner one of said Walls and a metallic sheathing covering said insulating material and also abutting the oifset in the inner one of said walls, the surface of said sheathing being flush With the inner surface of the twyer thereby forming a substantially smooth and continuous inner duct.

JAMES W. MILLER. p MICHAEL WEBB.

W'itnesses:

LUELLA A. COWING, GEO. J. CoWING. 

